Polyaniline derivatives and their production process

ABSTRACT

Novel polyaniline derivatives soluble in general organic solvents are provided without impairment of the inherent good properties of the corresponding polyanilines. The novel polyaniline derivatives are polymers represented by the following formula (I): ##STR1## wherein Y means a group represented by the following formula: R 1  CO--, R 2  S--, R 2  SO--, R 2  SO 2  -- or R 5  .paren open-st.O--R 4  .paren close-st. k  --OR 3  --, R 1  through R 5  being particular substituent groups, k is an integer of 0-5, and n and m independently represent polymerization degree and are integers satisfying the following equations: m/(n+m)=0.01-1 and n+m=20-1000. They can each be produced by reacting a halide, which is represented by the following formula: Y--X wherein Y has the same meaning as described above and X means a chlorine or bromine atom, to a reduced polyaniline.

This application is a continutation of application Ser. No. 07/693,867,filed Apr. 30, 1991, now U.S. Pat. No. 5,254,670.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel polyaniline derivatives solublein organic solvents and also to their production process.

2. Description of the Related Art

Investigation has been conducted in recent years with a view towardapplying polyanilines as new electronic materials or electroconductivematerials in a wide variety of fields such as cell electrode materials,antistatic materials, electromagnetic shielding materials, functionaldevices--e.g., photoelectric transducers, optical memories and varioussensors-, display devices, various hybrid materials, transparentelectroconductors, and various terminal equipment.

Polyanilines however have a highly developed π-conjugated system. Theyare hence accompanied by the serious drawbacks that they are insolublein most organic solvents and do not melt even when heated due to havinga rigid main chain and the existence of strong interaction and manystrong hydrogen bonds between polymer chains and also have poormoldability and permit neither cast molding nor coating.

They are therefore formed, for example, into electroconductive compositematerials by impregnating base materials of a desired shape--such asfibers, porous bodies or the like of high-molecular materials --withtheir corresponding aniline monomers and then bringing the monomers intocontact with a suitable polymerization catalyst or subjecting themonomers to electropolymerization to polymerize the monomers. As analternative, such aniline monomers are polymerized in the presence ofpowder of a thermoplastic polymer to obtain similar composite materials.

In the meantime, polyanilines soluble in N-methyl-2-pyrrolidone alonehave also been synthesized by suitably choosing the polymerizaitoncatalyst and reaction temperature [M. Abe et al.: J. Chem. Soc., Chem.Commun., 1736 (1989)]. These polyanilines are however practicallyinsoluble in other general organic solvents so that their applicationfield is limited.

SUMMARY OF THE INVENTION

The present invention has been completed with a view toward overcomingthe problems described above. An object of the present invention istherefore to provide a novel polyaniline derivative, which is soluble ingeneral organic solvents, without impairment of the good inherentproperties of the corresponding polyaniline. Another object of thepresent invention is to provide a process for producing the novelpolyaniline derivatives.

The present inventors have carried out an extensive investigation with aview toward overcoming the problems described above. As a result, it hasbeen found that these problems can be overcome by introducing aparticular substituent group to one or more nitrogen atoms of thepolyaniline, leading to the completion of the present invention.

Each polyaniline derivative according to the present invention is anovel polymer and is represented by the following formula (I): ##STR2##wherein Y means a group represented by the following formula: R₁ CO--,R₂ S--, R₂ SO--, R₂ SO₂ -- or R₅ .paren open-st.O--R₄ .parenclose-st._(k) --OR₃ --, R₁ being a substituted or unsubstituted alkylgroup having at least 4 carbon atoms, a cycloalkyl group having at least4 carbon atoms or an alkenyl group having at least 4 carbon atoms, R₂being a substituted or unsubstituted alkyl group having at least 2carbon atoms, a substituted or unsubstituted alkenyl group, asubstituted or unsubstituted aryl group or a substituted orunsubstituted benzyl group, R₃ being a linear or branched alkylene grouphaving 1-22 carbon atoms, R₄ being a linear or branched alkylene grouphaving 1-22 carbon atoms, R₅ being a substituted or unsubstituted alkylgroup having 1-22 carbon atoms or a cycloalkyl group, and k is aninteger of 0-5, and n and m independently represent polymerizationdegrees and are integers satisfying the following equations:m/(n+m)=0.01-1 and n+m=20-1000.

The above polyaniline derivatives of the present invention can beproduced in the following manner. Namely, a halide represented by thebelow-described general formula (II) is reacted to a reduced polyanilineto introduce a residual group of the halide as a substituent group toone or more nitrogen atoms of the reduced polyaniline:

    Y--X                                                       (II)

wherein Y has the same meaning as defined above and X is a bromine orchlorine atom.

Described in more detail, a polyaniline is treated with ammonia toconvert the polyaniline to a soluble polyaniline, which is then treatedwith excess hydrazine to convert it to a reduced polyaniline. After thereduced polyaniline is thereafter dissolved in an amide solvent ordispersed in an aromatic solvent or an ether solvent, the haliderepresented by the above formula (II) is added to introduce thesubstituent group to one or more of the nitrogen atoms of the reducedpolyaniline.

The production process of the present invention permits directintroduction of the substituent group to one or more of the nitrogenatoms of the reduced polyaniline so that the substituent group can beintroduced in a desired proportion. A polyaniline derivative, which issoluble in organic solvents and has excellent processability such asfilm formability or coating applicability, can therefore be producedwithout impairment of the inherent good properties of the correspondingpolyaniline.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention will hereinafter be described in detail.

Usable for the production of the polyaniline derivative according to thepresent invention a polyaniline is provided which has been obtained byoxidative polymerization of aniline using ammonium persulfate or thelike as oxidizing agents at a low temperature, for example, in the rangeof from -20° C. to 50° C. and which has a polymerization degree of20-1000, preferably 50-200. First of all, the polyaniline is treatedwith ammonia to convert it to a soluble polyaniline. The solublepolyaniline is then treated with excess hydrazine to prepare a reducedpolyaniline. The term "reduced polyaniline" means a reduced product ofthe above polyaniline as obtained by the oxidative general organic, saidreduced product containing a hydrogen atom bonded to each of allnitrogen atoms contained in the polyaniline. The hydrazine treatment canbe effected by dispersing the soluble polyaniline in water, addinghydrazine in an amount at least equivalent to, preferably three timesthe nitrogen atoms in the polyaniline in a nitrogen atmosphere and thenstirring the resultant mixture at 0°-30° C. for 24 hours.

The reduced polyaniline thus obtained is soluble inN-methyl-2-pyrrolidone or N,N-dimethylacetamide but is practicallyinsoluble in other generalorganic solvents, for example, chloroform andtetrahydrofuran.

Next, the halide represented by the formula (II) is caused to act on thereduced polyaniline to effect a substitution reaction. The substitutionreaction can be conducted by dissolving the reduced polyaniline in anamide solvent or dispersing it in an aromatic solvent or ether solvent,adding the halide represented by the formula (II) to the resultantsolution or dispersion and then stirring the thus-obtained mixture in atemperature range of from -10° C. to 100° C. in a nitrogen atmosphere.

Usable, exemplary amide solvents include N-methyl-2-pyrrolidone,N,N-dimethylacetamide, N,N-dimethylformamide, hexamethyl phosphorictriamide and 1,3-dimethyl-2-imidazolidinone. Usable, illustrativearomatic solvents include benzene, toluene, xylene, ethylbenzene andtetralin. On the other hand, usable examples of the ether solventinclude ether, tetrahydrofuran and dioxane.

Examples of the halide represented by the formula (II) include compoundsrepresented by the following formulae (IIA)-(IIE), respectively:

    ______________________________________                                        R.sub.1 COX             (IIA)                                                 R.sub.2 SX              (IIB)                                                 R.sub.2 SOX             (IIC)                                                 R.sub.2 SO.sub.2 X      (IID)                                                 R.sub.5 (O--R.sub.4 ) .sub.k OR.sub.3 --X                                                             (IIE)                                                 ______________________________________                                    

wherein R₁, R₂, R₃, R₄, R₅, X and k have the same meanings as definedabove.

Examples of R₁ in the acyl halide represented by the formula (IIA)include linear alkyl groups such as butyl, pentyl, hexyl, heptyl, octyl,nonyl, decyl, undecyl, dodecyl, hexadecyl and docosyl; branched alkylgroups such as isobutyl, isopentyl, neopentyl and isohexyl; cyclic alkylgroups such as cyclohexyl; and alkenyl groups such as butenyl, pentenyland hexenyl. One or more of the hydrogen atoms of these groups may besubstituted by a like number of halogen atoms and/or cyano, nitro,phenyl, alkoxyl and/or hydroxyl groups.

Examples of R₂ in the sulfenyl halide, sulfinyl halide and sulfonylhalide represented by the formulae (IIB)-(IID), respectively, includethe following groups:

Substituted or unsubstituted alkyl groups having 2 or more carbon atoms,for example, linear alkyl groups such as ethyl, propyl, butyl, pentyl,hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, hexadecyl anddocosyl; branched alkyl groups such as isobutyl, isopentyl, neopentyland isohexyl; and those obtained by substituting one or more of theirhydrogen atoms with a like number of halogen atoms and/or cyano, nitro,alkoxyl and hydroxyl groups.

Exemplary, substituted or unsubstituted alkenyl groups include butenyl,pentenyl and hexenyl groups and those obtained by substituting one ormore of their hydrogen atoms by a like number of alkyl, phenyl, cyano,nitro and/or hydroxyl groups and/or halogen atoms.

Illustrative, substituted or unsubstituted aryl groups include a phenylgroup and those obtained by substituting one or more of the hydrogenatoms of a phenyl group with a like number of halogen atoms and/orcyano, nitro, alkoxyl and/or hydroxyl groups.

Examples of one or more substituent groups in the substituted benzylgroup include halogen atoms and/or cyano, nitro and akoxyl groups.

Examples of R₃ and R₄ in the halogenated alkyl ether or halogenatedpolyalkyl ether represented by the formula (IIE) include linear orbranched alkylene groups having 1-22 carbon atoms, with methylene,ethylene and propylene groups being preferred. Further,illustrativeexamples of the substituted or unsubstituted alkyl or cyclo alkyl grouphaving 1-22 carbon atoms include linear alkyl groups such as methyl,ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl,undecyl, dodecyl, hexadecyl and docosyl; branched linear alkyl groupssuch as isobutyl, isopentyl, neopentyl and isohexyl; and a cyclohexylgroup. They may contain, for example, one or more cyano, nitro and/orhydroxyl groups.

Preferred, specific examples of the acyl halide represented by theformula (IIA) include 1-octanoyl chloride, 1-hexanoyl chloride and2-methylheptanoyl chloride.

Preferred, specific examples of the sulfenyl halide represented by theformula (IIB) include 1-octanesulfenyl chloride, p-toluenesulfenylchloride and o-nitrophenylsulfenyl chloride.

Preferred, specific examples of the sulfinyl halide represented by theformula (IIC) include 1-butanesulfinyl chloride, 1-octanesulfinylchloride, p-toluenesulfinyl chloride, benzylsulfinyl chloride andbenzenesulfinyl chloride.

Preferred, specific examples of the sulfonyl halide represented by theformula (IID) include 1-butanesulfonyl chloride, 1-octanesulfonylchloride, p-toluenesulfonyl chloride, benzylsulfonyl chloride andbenzenesulfonyl chloride.

Further, preferred, specific examples of the halogenated alkyl ether orhalogenated polyalkyl ether represented by the formula (lIE) include2-bromoethyl ethyl ether, diethylene glycol bis(2-chloroethyl)ether, andpolyethylene glycol bts(2-bromoethyl)ether (k=5).

In the present invention, the substitution reaction by the halide can beconducted preferably in such a manner that substituent groups can beintroduced to at least 1% of the nitrogen atoms of the reducedpolyaniline.

It is desirable to subject the N-substituted polyaniline derivative,which has been obtained as described above, to undoping treatment as apost treatment with aqueous ammonia.

Each polyaniline derivative according to the present invention, whichcan be produced as described above, is represented by the formula (I)and is soluble not only in N-methyl-2-pyrrolidone andN,N-dimethylacetamide but also in halogenated hydrocarbon solvents suchas chloroform, dichloroethane and dichlor omethane and ether solventssuch as tetrahydrofuran. Using a solution of the polyaniline in one ofthese solvents, a good self-standing film can be obtained by casting.The films so formed shows conductivity as high as 10⁻³ -10¹ S/cm afterit has been doped in a protonic acid such as hydrochloric acid, sulfuricacid, fluoboric acid or perchloric acid.

The hue of each novel polyaniline derivative of the present inventionvaries depending on the polarity of each solvent, thereby making itpossible to use the polyaniline derivative as a polarity indicatormaterial for solvents. The hue also varies depending on the hydrogen ionconcentration, so that the polyaniline derivative can also be used as ahydrogen ion detector.

The present invention will hereinafter be described by followingexamples.

EXAMPLES Example 1

Aniline (4.1 g) and concentrated hydrochloric acid (21.9 g) weredissolved in water to give an aniline solution (100 ml). The anilinesolution was chilled to -5° C. Concentrated hydrochloric acid (21.9 g)and ammonium persulfate (6.28 g) were also dissolved in water to give asolution (100 ml). The latter solution was also chilled to -5° C. andwas then slowly added dropwise to the aniline solution, followed bystirring at -5° C. for 4 hours. The thus-obtained polyaniline having anumber average molecular weight of 12,000 (as measured by GPC inN-methyl-2-pyrrolidone as a solvent and converted relative topolystyrene) was washed thoroughly with water, followed by undopingtreatment with aqueous ammonia.

The resulting soluble polyaniline was dispersed in water (200 ml),followed by the addition of hydrazine (50 ml) in a nitrogen atmosphere.The mixture thus obtained was continuously stirred for 24 hours at roomtemperature. The resultant solid precipitate was collected by filtrationand then dried, whereby a reduced polyaniline of a grayish white colorwas obtained.

The reduced polyaniline (1 g) so obtained was completely dissolved inN-methyl-2-pyrrolidone (20 ml). After the reaction system having beenthoroughly purged with nitrogen gas, octanoyl chloride (0.5 g) wasadded. The mixture was stirred for 6 hours so that they were reacted.The reaction mixture was poured into water (1 liter) while the resultingmixture was stirred. The resulting precipitate was collected byfiltration, dried and then subjected to undoping treatment with aqueousammonia, whereby a polyaniline derivative with amidated nitrogen atomswas obtained in an amount of 1.3 g. The amidation of the reducedpolyaniline was confirmed by the existence of an absorption at 1660 cm⁻¹in an infrared absorption spectrum. From the yield of the reaction, thedegree of substitution at the nitrogen atoms was found to be 30%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassatisfactorily obtained by casting. Its conductivity was 0.1 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 2

A polyaniline derivative with amidated nitrogen atom (1.15 g) wasobtained in a similar manner to Example 1 except that 1-hexenoyl bromide(0.2 g) was used in lieu of octanoyl chloride. The amidation of thereduced polyaniline was confirmed by the existence of an absorption at1660 cm⁻¹ in an infrared absorption spectrum. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 13%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 3

A polyaniline derivative with amidated nitrogen atoms (1.15 g) wasobtained in a similar manner to Example 1 except that 2-methylheptanoylchloride (0.2 g) was used in lieu of octanoyl chloride. The amidation ofthe reduced polyaniline was confirmed by the existence of an absorptionat 1660 cm⁻¹ in an infrared absorption spectrum. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 11%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.03 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 4

A reduced polyaniline (1 g) obtained in a similar manner to Example 1was completely dissolved in N-methyl-2-pyrrolidone (30 ml). After thereaction system having been thoroughly purged with nitrogen gas,p-toluenesulfenyl chloride (0.87 g; 50 mol % relative to the nitrogenatoms of the reduced polyaniline) was added, followed by stirring for 6hours so that they were reacted. The reaction mixture was poured intowater (1 liter) while the resulting mixture was stirred. The resultingprecipitate was collected by filtration, dried and then subjected toundoping treatment with aqueous ammonia, whereby a polyanilinederivative with sulfenamidated nitrogen atoms was obtained in an amountof 1.5 g. When the polyaniline derivative thus obtained was analyzed byinfrared absorption spectroscopy, an absorption of 2955 cm⁻¹ by themethyl groups of the substituted toluenesulfenyl groups was observed.From the yield of the reaction, the degree of substitution at thenitrogen atoms was found to be 37%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.01 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 5

A polyaniline derivative with sulfenamidated nitrogen atoms (1.7 g) wasobtained in a similar manner to Example 4 except thato-nitrophenylsulfenyl chloride (1.04 g; 50 mol % relative to thenitrogen atoms of the reduced polyaniline) was used in lieu ofp-toluenesulfenyl chloride. When the resultant polyaniline derivativewas analyzed by infrared absorption spectroscopy, absorptions at 1520cm⁻¹ and 1345 cm⁻¹ by nitro groups were observed. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 47%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.01 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 6

A polyaniline derivative with sulfenamidated nitrogen atoms (1.4 g) wasobtained in a similar manner to Example 4 except that 1-octanesulfenylchloride (0.99 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfenyl chloride. When theresultant polyaniline derivative was analyzed by infrared absorptionspectroscopy, an absorption at 2955 cm⁻¹ by methyl groups and that at2930 cm⁻¹ by methylene groups were observed. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 25%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 7

A reduced polyaniline (1 g) obtained in a similar manner to Example 1was completely dissolved in N-methyl-2-pyrrolidone (30 ml). After thereaction system having been thoroughly purged with nitrogen gas,p-toluenesulfinyl chloride (0.96 g; 50 mol % relative to the nitrogenatoms of the reduced polyaniline) was added, followed by stirring for 6hours so that they were reacted. The reaction mixture was poured intowater (1 liter) while the resulting mixture was stirred. The resultingprecipitate was collected by filtration, dried and then subjected toundoping treatment with aqueous ammonia, whereby a polyanilinederivative with sulfinamidated nitrogen atoms was obtained in an amountof 1.5 g. When the polyaniline derivative thus obtained was analyzed byinfrared absorption spectroscopy, an absorption of 2955 cm⁻¹ by themethyl groups of the substituted toluenesulfinyl groups was observed.From the yield of the reaction, the degree of substitution at thenitrogen atoms was found to be 33%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.01 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 8

A polyaniline derivative with sulfinamidated nitrogen atoms (1.4 g) wasobtained in a similar manner to Example 7 except that 1-butanesulfinylchloride (0.78 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfinyl chloride. When theresultant polyaniline derivative was analyzed by infrared absorptionspectroscopy, an absorption at 2955 cm⁻¹ by methyl groups and that at2930 cm⁻¹ by methylene groups were observed. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 34%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 9

A polyaniline derivative with sulfinamidated nitrogen atoms (1.6 g) wasobtained in a similar manner to Example 7 except that 1-octanesulfinylchloride (1.1 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfinyl chloride. When theresultant polyaniline derivative was analyzed by infrared absorptionspectroscopy, an absorption at 2955 cm⁻¹ by methyl groups and that at2930 cm⁻¹ by methylene groups were observed. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 34%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 10

A polyaniline derivative with sulfinamidated nitrogen atoms (1.3 g) wasobtained in a similar manner to Example 7 except that 1-benzylsulfinylchloride (0.96 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfinyl chloride. When theresultant polyaniline derivative was analyzed by infrared absorptionspectroscopy, an absorption at 2940 cm⁻¹ by methylene groups wasobserved. From the yield of the reaction, the degree of substitution atthe nitrogen atoms was found to be 20%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 11

A reduced polyaniline (1 g) obtained in a similar manner to Example 1was completely dissolved in N-methyl-2-pyrrolidone (30 ml). After thereaction system having been thoroughly purged with nitrogen gas,p-toluenesulfonyl chloride (1 g; 50 mol % relative to the nitrogen atomsof the reduced polyaniline) was added, followed by stirring for 6 hoursso that they were reacted. The reaction mixture was poured into water (1liter) while the resulting mixture was stirred. The resultingprecipitate was collected by filtration, dried and then subjected toundoping treatment with aqueous ammonia, whereby a polyanilinederivative with sulfonamidated nitrogen atoms was obtained in an amountof 1.5 g. The sulfonamidation was confirmed by absorptions at 1350 cm⁻¹and 1160 cm⁻¹ in an infrared absorption spectrum. From the yield of thereaction, the degree of substitution at the nitrogen atoms was found tobe 29%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.01 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 12

A polyaniline derivative with sulfonamidated nitrogen atoms (1.1 g) wasobtained in a similar manner to Example 11 except that 1-butanesulfonylchloride (1.1 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfonyl chloride. Thesulfonamidation was confirmed by absorptions at 1350 and 1160 cm⁻¹ in aninfrared absorption spectrum. From the yield of the reaction, the degreeof substitution at the nitrogen atoms was found to be 30%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 13

A polyaniline derivative with sulfonamidated nitrogen atoms (1.6 g) wasobtained in a similar manner to Example 11 except that 1-octanesulfonylchloride (1.2 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfonyl chloride. Thesulfonamidation was confirmed by absorptions at 1350 and 1160 cm⁻¹ in aninfrared absorption spectrum. From the yield of the reaction, the degreeof substitution at the nitrogen atoms was found to be 30%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 14

A polyaniline derivative with sulfonamidated nitrogen atoms (1.3 g) wasobtained in a similar manner to Example 11 except that benzylsulfonylchloride (1 g; 50 mol % relative to the nitrogen atoms of the reducedpolyaniline) was used in lieu of p-toluenesulfonyl chloride. Thesulfonamidation was confirmed by absorptions at 1350 and 1160 cm⁻¹ in aninfrared absorption spectrum. From the yield of the reaction, the degreeof substitution at the nitrogen atoms was found to be 18%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 15

A reduced polyaniline (1 g) obtained in a similar manner to Example 1was completely dissolved in N-methyl-2-pyrrolidone (30 ml). After thereaction system having been thoroughly purged with nitrogen gas,2-bromoethyl ether ether (0.5 g) was added, followed by stirring for 6hours so that they were reacted. The reaction mixture was poured intowater (1 liter) while the resulting mixture was stirred. The resultingprecipitate was collected by filtration, dried and then subjected toundoping treatment with aqueous ammonia, whereby an N-substitutedpolyaniline derivative was obtained in an amount of 1.2 g. When thepolyaniline derivative thus obtained was analyzed by infrared absorptionspectroscopy, an absorption of 2950 cm⁻¹ by methylene groups of thesubstituents was observed. From the yield of the reaction, the degree ofsubstitution at the nitrogen atoms was found to be 29%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 1.0 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 16

A polyaniline derivative with sulfonamidated nitrogen atoms (1.1 g) wasobtained in a similar manner to Example 15 except that diethyleneglycolbis(2-chloroethyl)ether (0.2 g) was used in lue of 2-bromoethyl ether.When thus-obtained polyaniline derivative was analyzed by infraredabsorption spectroscopy, an absorption at 2950 cm⁻¹ by methylene groupwas observed. From the yield of the reaction, the degree of substitutionat the nitrogen atoms was found to be 7%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.05 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Example 17

A polyaniline derivative with ether groups substituent (1.1 g) wasobtained in a similar manner to Example 15 except thatpolyethyleneglycol bis(2-bromoethyl) ether (n=5) (0.1 g) was used inlieu of 2-bromoethyl ethyl ether. When the thus-obtained polyanilinederivative was analyzed by infrared absorption spectroscopy, anabsorption at 2950 cm⁻¹ by methylene groups was observed. From the yieldof the reaction, the degree of substitution at the nitrogen atoms wasfound to be 2%.

The polyaniline derivative was soluble in N-methyl-2-pyrrolidone andalso showed high solubility in organic solvents such as chloroform,dichloroethane, dichloromethane and tetrahydrofuran. From a solution ofthe polyaniline derivative in chloroform, a self-standing film wassuccessfully obtained by casting. Its conductivity was 0.5 S/cm afterhaving been doped with sulfuric acid.

Further, the film before the doping was successfully dissolved inorganic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide,chloroform, dichloroethane, dichloromethane and tetrahydrofuran.

Comparative Example

Aniline (4.1 g) and concentrated hydrochloric acid (21.9 g) weredissolved in water to give an aniline solution (100 ml). The anilinesolution was chilled to -5° C. Concentrated hydrochloric acid (21.9 g)and ammonium persulfate (6.28 g) were also dissolved in water to give asolution (100 ml). The latter solution was also chilled to -5° C. andwas then slowly added dropwise to the aniline solution, followed bystirring at -5° C. for 4 hours. The thus-obtained polyaniline was washedthoroughly with water, followed by undoping treatment with aqueousammonia.

The polyaniline thus obtained was soluble in N-methyl-2-pyrrolidone, anda self-standing film was successfully obtained from a solution ofpolyaniline in N-methyl-2-pyrrolidone. However, the polyaniline wasinsoluble in chloroform or tetrahydrofuran. Moreover, the self-standingfilm thus obtained was not soluble in any organic solvents.

I claim:
 1. A polyaniline comprising units of the following formula:##STR3## wherein Y defines a group represented by the following formula:R₁ CO--, R₁ being a cycloalkyl group having at least 4 carbon atoms oran alkenyl group having at least 4 carbon atoms or 2-methyl heptyl, andn and m independently represent polymerization degrees and are integerssatisfying the following equations:

    m/(n+m)=0.01 to 1;

and

    n+m=20 to 1000,

said polyaniline being soluble in organic solvents.
 2. A polyanilineconsisting of units of the following formula: ##STR4## wherein Y definesa group represented by the following formula: R₁ CO--, R₁ being acycloalkyl group having at least 4 carbon atoms or an alkenyl grouphaving at least 4 carbon atoms or 2-methyl heptyl, and n and mindependently represent polymerization degrees and are integerssatisfying the following equations:

    m/(n+m)=0.01 to 1;

and

    n+m=20 to 1000,

said polyaniline being soluble in organic solvents.
 3. The polyanilinederivative of claim 1 or 2, wherein R₁ is 1-hexenyl or 2-methyl heptyl.